Apparatus for making prints



Aug. 22, 1961 E. P. TAUBES APPARATUS FOR MAKING PRINTS 5 Sheets-Sheet 1 Filed Aug. 8, 1958 .fl m 7 IA n T P a T n S Aug. 22, 1961 E. P. TAUBES APPARATUS FOR MAKING PRINTS 5 Sheets-Sheet 2 Filed Aug. 8, 1958 FIG?) INVENTOR. ERNEST P. TAUBES liiorny Aug. 22, 1961 E. P. TAUBES APPARATUS FOR MAKING PRINTS 3 Sheets -Sheet 3 Filed Aug. 8, 1958 FIG.8

INVENTOR. ERNEST F. TAUBES At orney fi United States Patent York Filed Aug. 8, 1958, Ser. No. 253,973 12 Claims. (Cl. 101-1315) This invention relates. to a copier or duplicator, and more particularly to. improved apparatus for developing a matrix and for contact-copying from the matrix.

In present duplicating practice, matrix paper having an emulsified surface composedv of the, suspension of a silver halide developer'and dye forming; components, for example, is exposed for a predetermined length of. time in contact with the original material of which copies are desired to be made; the exposed matrix is then removed and inserted into a tray containing a liquid activator or developer which chemically activates the. exposed. matrix. The copy paper and the emulsifiedv surface of the exposed and developed or activated matrix arev then manually brought in contact with each other and drawn by hand through a squeegee blade and pressure bar, to transfer the copy material from the developed matrix to the copy paper. The copy paper is then peeled from the developed matrix. In order to make another copy, the exposed matrix is again manually immersed in the. ac,- tivating solution, and another piece of, blank copy paper and the matrix are drawn through the squeegee blade and pressure rollerto bring the developed surface of the matrix and the copy paper in firm contact. This entire operation is repeated until the required number of, copies are obtained, or until the matrix is no longer able to eifect a legible transfer.

In practice, in. order to successfully reproduce a plurality of copies from a single matrix, it is necessary to reinsert the matrix in the developer solution and perform the squeegee contact operation with great rapidity, to obtain the greatest number of copies before the emulsion hardens, as the hardening of the emulsion. rendersa legible transfer impossible. It is also important that the matrix, when reinserted in the activating solution, re.- main in the solution the shortest lengthof, time: possible when making additional copies. With conventionalapparatus, each time the matrix, is peeled from the copy paper its emulsionv is exposed to the air, which tends to unduly accelerate the hardening process of the exposed areas of the matrix. Furthermore, the actual mechanics of reinserting the matrix in the developing-solution, and manually bringing a separate; sheet ofcopy paper in contact with the matrix, takes time, and prevents the. making of copies with rapidity.

The emulsified surface of the developed matrix and they surface of the copy paper tend to strongly adhere to each other after being pressed together. Therefore, in accordance with present practice it is necessary to] provide a matrix paper with anIunemulsified leading edge, which edge does not adhere to the,copy paper, so that during the peeling operation, as, aforementioned', the. op..- erator may grasp the unemulsified edge of the matrix paper and thecorresponding edge of the copypaper, and readily peel them apart. The manufacture of. a, matrix with a portion of its surface unemul'sified is an. expensive operation.

In view of the above, one of the objects of the. pres ent invention is to provide an, apparatus which will more effectively print a plurality of copies from the same exposed and developed'matrix.

Another object of this invention is to provide an. improved apparatus which will make more copies from a single-exposed and developedmatrix.

Another object of -this invention isto provide an imice 2 proved apparatus. wherein additional copies may be made from the same exposed and developed matrix without manually reinserting and withdrawing the matrix from the developing solution each time a copy is to be made.

Another object of this invention is to provide an improved apparatus which requires minimum exposure. of the developed matrix to the air.

A further object of this invention is to provide an im-. proved apparatus having a drum contact surface for bringing the matrix and the copy paper in contact.

A, further. object of this invention is to provide an improved apparatus which will print a plurality of copies from a single matrix, and from copy paper in the form of a continuous roll.

A still further object of this invention is to provide a drum type apparatus for copying from. an emulsified surface, and having improved means for securing the exposed and developed matrix onto the surface of a contact drum.

A still further object of this invention is to provide an improved apparatus for copying from an emulsified matrix paper which does not require that the emulsified matrixpaper have an unemulsified edge.

A still. further object of this invention is to provide an. improved. apparatus which permits the matrix paperfrom whichecopies are made, to be in a continuous roll. form.

A still further object of this invention is to provide an: improved apparatus for developing the exposed matrix in; the chemical developing solution.

A still further object of this invention is to provide an improved copying apparatus which is compact int size, simple in its operation, and economical to manufacture.

Other objects, purposes, and characteristic features of" this invention will become apparent from the drawings the specification, and the appended claims.

In the drawings:

FIG. 1 is a perspective view of one embodiment of' this, invention, which is cut away to show its interior mechanism;

FIG. 2 is a plan view of this embodiment of the in-- vention;

FIG. 3 is a side elevation of the apparatus, part being broken away to show the operating mechanism;

FIGL4 is a cross-sectional view taken on the line. 4.-4 ofFIG. 2 looking in the direction of the arrows;

FIG. 5 is a diagrammatic view of this embodiment of the. invention showing the apparatus in position to clamp amatrix to its drum;

FIG. 6 is a diagrammatic view of the drumwith the matrixclamped'securely thereto;

FIG. 7 is a diagrammatic view of the drumwith the; matrix. partially spread on the surface of the drum;

FIG. 8, is a diagrammatic view showing the positionof" the. drum, withthe matrix on its surface and with. copy' paper in initial contact with the matrix;

FIG. 9 is a diagrammatic view showing the relative position of the matrixand the copy paper nearthe. end of a copying operation; and

FIG. 10. is a fragmentary view taken onthe 1ine10- 10'of;EI;G1 2, looking in the direction of'the arrows.

embodimentof the invention comprises a rec-.- tangular developing tray 10 having spaced. longitudinally extending supporting ridges 11 formed in its bottom sur-- face. The tray 10 is provided with a cover 12, which has; longitudinally downward extending guides 13 along its; undersurface. The upper edges of the supporting ridges; 11 and the. downwardly. extending guides 13 are vertically spaced from each other to form a guideway 23' (see FIG. 4),,which extends transversely from one side of'thetray' 10 to the other, and from a point near the rear of tray to the front. The guideway slants upward at its front or forward end, because of the slanting cooperating surfaces of the downward extending guides 13 and the supporting ridges 11. The guideway 23 terminates in a mouth 14 in the top front portion of the tray 10, which mouth is coextensive with the width of the guideway 23. A guide roller 22 is rotatably mounted in the tray between brackets 61, which are formed integrally with the cover 12 and on each side of the guide members 13. The peripheral surface of the guide roller 22 extends a predetermined distance above the edges of the supporting ridges 11 at the rear of the guideway 23.

The rear of the tray is provided with a hinged cover 24 which is adapted to be opened to admit a developing solution into the interior of the tray. The tray is adapted to be filled with the developing solution until it completely covers the guideway 23 and attains a height just below the mouth 14 at the front of the tray 10. A developing solution heating element 17 (FIG. 4) is attached totthe bottom of the tray 10 and is operably connected to a thermostat 18 which controls the energizing element 20 for maintaining the developing solution at the proper 7 to the housing and the plate 15' respectively.

temperature. A switch 21 is mounted on the cover 12 for selectively turning the heating element. 17 on or off.

The rear portion of the developing tray 10 is provided with a housing 15 and a supporting plate 15 (FIG. 1), one of which is mounted on each of the opposite sides of the tray 10. Rotatably attached between the housing 15 and the supporting plate 15' is a drum 25 which is so disposed that a portion of its circumference is adapted to be continually immersed in the developing solution in the tray 10. The circumferential surface of the drum 12 is disposed above and in close proximity to the rear edges of the supporting ridges 11.

The cover 12 of the tray is provided with integrally formed angularly extending brackets 62 to which is attached a squeegee blade 19 which engages the surface of the drum 25 and wipes off any excess developing solution which may adhere to the surface of the drum and the matrix during its rotating operation.

The surface of the drum 25 is provided with a recess 72 (FIG. 10) which extends parallel to its axis. Adjoining this recess is a groove 73 of increased depth which also extends axially of the drum 25 but preferably is shorter than recess 72 and is disposed centrally of the drum length. A matrix securing clamp 26 is pivotally mounted on the surface of the drum 25 in the axial recess 72 by means of a rod 74 which is welded or brazed to the clamp. When the clamp 26 is open it extends outward from the surface of the drum 25 and when the clamp 26 is closed, it.is positioned substantially flush with the surface of the drum 25. The clamp 26 serves to clamp the leading edge of an exposed matrix securely to the periphery of the drum 25 when the clamp 26 is in its flush position. A locln'ng rod 27 (FIGS. 1 and 4 to 9 inclusive) is attached at one end to the clamp 26 and extends normal to the pivotal axis of the clamp. A spring 28 is tensionally secured to the locking rod 27 and to one end of the drum 25. It permits the clamp 26 and the rod 27 to be spring-biased to either an open or a closed clamping position in accordance with the position of the rod 27.

The end of the rod 27 opposite that which carries the clamp 26 is provided with an extension 29 which is adapted to be engaged by an actuating pin 31, which is secured to the inner side of the plate 15. The pin 31 is provided to snap the locking rod 27 counterclockwise, as viewed in the drawings, to operate the member 26 to its clamping position. The hinged filling cover 24 is provided with a clamp opener 16 which is pivotally mounted thereon. The clamp opener 16 is adapted to fit beneath the clamp 26 into the groove 73 in the surface ofthe drum to open the clamp out of clamping position.

- A feed roller assembly comprising a feed roller 30 and 60, for example, onto the surface of the drum. The feed 4 roller 30 is horizontally and rotatably mounted at opposite ends in the housing 15 and the supporting plate 15', respectively, so that its peripheral surface is spaced a short distance from the surface of the drum 25. The feed friction roller 35 is horizontally and rotatably mounted at opposite ends in the housing 15 and the supporting plate 15, respectively, above the feed roller 30 and in frictional engagement therewith. The friction roller 35 is urged downward in frictional engagement with the feed roller 30 by means of helical springs 75 (FIG. 10).

A pressure roller 33 is rotatably mounted between arms 77 which are pivotally attached at opposite eggs e pressure roller 33 is urged downward against the surface of the drum 25 by pressure of springs 76 against the pivotally mounted arms 77. The springs 76 are interposed between the arms 77 and the heads of screws 78, which thread into the arms and seat against the plate 15 and the housing 15, respectively. The pressure roller 33 serves to press the copy paper 60 in firm contact with the matrix on the surface of the drum. This copy paper may be supplied from a roll supported in any suitable manner on the apparatus. The apparatus may be used, also, however, for making prints on individual sheets of copy paper.

The drum has a journal which projects into housing 15 and secured to this journal within the housing coaxially of the drum is a spur gear 36 (FIGS. 2 and 3). A driving spur gear 37 is mounted in the housing in mesh with the gear 36 and is coaxially attached to a crank handle 38 which projects outside the housing. A gear 41, which is coaxially attached to the fed roller 30 within the housing 15, meshes with an idler gear 42, which is also mounted rotatably within the housing 15. The idler gear 42 is mounted on one arm of a bell crank 43. The bell crank 43 is pivotally mounted coaxially with the feed roller 30 between the gear 41 and the outside wall of the housing 15. A lever 46, that is pivotally mounted intermediate its ends on a pivot pin 47 within the housing 15, is connected by a link 45 with the other arm 44 of the bell crank 43. When the gear 42 meshes with gear 36 it is driven by the gear 36, while the gear 42 in turn drives the gear 41 for rotating the feed roller 30. The ratio of the gears 42 and 41 relative to the gear 36, and the diameter of the feed roller 30 are so chosen that the surface of the feed roller 30 moves at the same peripheral speed as the surface of the drum 25 during rotation. The lever 46, when depressed, rocks the gear 42 out of mesh with the drum gear 36. When the gear 42 is out of mesh with gear 36, the feed roller 30 and consequently the feed friction roller 35 are stationary.

A spring biased dog 48 is pivotally mounted within the housing 15 by a pin 49. The dog 48 is constantly urged clockwise, as viewed in FIG. 3, by a spring 51. When the lever 46 is depressed, then, spring 51 rocks this dog into position to lock the bell crank 43 in position to maintain the gear 42 out of mesh with gear 36. A pin 52 attached to the housing 15 limits the clockwise swing of the dog 48 to locking position. The gear 36 is provided with an axially extending pin 39 which serves to engage the dog 48 when the drum is rotated in a counterclockwise direction, thereby rocking the dog out of engagement with the bell crank 43, and permitting the gear 42 to mesh with the gear 36. The pin 39 is so disposed on the surface of the gear 36 that when it engages the dog 48, the bell crank is released to permit gear 42 to mesh with the gear 36, to begin feeding the copy paper between the feed roller 30 and the friction roller 35 first before the clamp 26 reaches the position shown in FIG. 8 so that the lead end of the copy paper is positioned over the groove 73 on the surface ofthe drum and ahead of the enveloped surface of the matrix for a purpose which will appear hereinafter.

In operation, when the switch 21 (FIG. 3) is actuated, the thermostatically controlled heating element 17 is activated to bring the developing liquid to, and maintain it at, the proper temperature. To use the machine, the drum is rotated by crank 38 to bring the clamp 26 abreast of opener 16, and the opener 16 is pivoted to open the clamping member 26. The hinged cover portion 24 is then raised to permit the opened clamp to be rotated into the developing liquid in the tray. The crank 38 is then operated to rotate the drum counterclockwise, as viewed in FIG. 1, until the edge 70 (FIGS. 4 and 5) of the clamp 26 physically contacts the edge 71 of the ridges 11, thereby stopping further counterclockwise movement of the drum. This insures that a new matrix will be positioned on the drum in the same starting position as every other matrix. With the drum in this position, the space between the surface of the drum and the opened clamp 26 is aligned with the guideway 23 in the tray 10.

The lever 46 is at this time in its depressed position and the bell crank 43 at this time is held locked out by the dog 48, thereby rendering the gear 36 ineffective to drive the feed roller 30 during rotation of the drum. The exposed matrix 40, is then inserted through the mouth 14 at the front of the tray with its exposed emulsified surface facing up, and is moved rearward until it enters the space between the clamping member 26 and the periphery of the drum 25. The forward slanting portion of the guideway 23 guides the matrix downward into the developing solution in the guideway 23 between the guide members 13 and the supporting members 11 to the rear of the tray 10. The edges of the members 13 which serve as the top of the guideway prevent the matrix from rising to the surface of the developing fluid after it has been inserted in the tray.

The crank 38 is then turned counterclockwise a short distance to rotate the drum 25 clockwise until the extension 29 of the rod 27 engages the pin 31 (FIG. 5) which throws the rod 27 over center, thereby closing the member 26 lflllSh with the surface of the drum, which clamps the matrix 40 securely to the periphery of the drum 25 (FIG. 6).

After the matrix is clamped in position the drum is rotated a short distance in the same clockwise direction until the entire matrix is pulled into the developing liquid. After the exposed. matrix has been immersed for a sufiicient length of time, such as 20 seconds, for example, in the developing solution in the tray 10, with its leading edge clamped between the member 26 and the recess 72], the crank 38 is turned in a clockwise direction to move the drum 25 in a counterclockwise direction, thereby folding the matrix over the edge 70 of the clamping member 26 (FIG. 7), so that the emulsified surface of the matrix is on the outside of the drum. As the drum is rotated further counterclockwise, the matrix is wrapped around the drum 25, and the guide roller 22 assists in maintaining the surface of the matrix in a non-wrinkled or smooth condition. The squeeges blade 19 wipes off any excessive developing liquid so that it runs back into the tray 10.

The friction roller 35 may then be lifted against the pressure of its springs 75, and the forward end of the copy paper 60 may be inserted between the feed roller 30 and the friction roller 35.

When the drum is rotated counterclockwise a distance sufficient for the pin 39 to move the dog. 48 (FIG. 1) out of engagement with the bell crank 43, the gear '42 will mesh with the gear 36, and the feed roller 30 and the friction feed roller 35 begin rotating with drum 25. At this point, the forward end of the developed matrix is on that portion of the surface of the drum 25 near the feed roller 30. The lever 38 is then rotated in a clockwise direction which rotates the drum 25 counterclockwise so that its gear 36 drives the gear 42, to rotate the feed roller 30 which in turn rotates the friction roller 35, so that the copy paper 60 is fed under the pressure roller 33, and the copy paper 60 and the matrix 40 are pressed together between the pressure roller 33 and the surface of the drum 25 (FIG. 8). The feed roller 36 begins rotating soon enough for the leading edge of the copy paper 60 to be positioned on the surface of the drum 25 between the edge of the recess 72 and the edge of the clamping member 26 and over the groove 73. When the clamping member 26 reaches a position beyond the pressure roller 33, the edge of the copy paper 60 can be lifted from contact with the matrix 40 by inserting the fingers in the groove 73 and lifting upward. It is noted that the copy paper is so positioned on the surface of the drum that its leading edge is ahead of the emulsified surface of the matrix. This is important in that the copy paper can be easily peeled from the surface of the matrix, without requiring that the matrix have an unemulsified edge. It should also be noted that the length of the matrix should be less than the perimeter of the drum so that the rear edge of the matrix does not reach the recess portion 72 of the drum after being fully wrapped around the drum. During successive revolutions of the drum, the attached matrix is repeatedly immersed in the developing solution between each contact with copy paper. On each revolution a copy of the matrix is made on copy paper. The lever 38 is continually rotated clockwise until a sufiicient number of copies are made, or until the matrix no longer produces satisfactory copies. A knife or other paper severing means (not shown) would be conveniently mounted on the apparatus to cut the used copy paper from the roll. Thus, it is apparent that a plurality of copies can be efiiciently printed without handling the developed matrix.

While the invention has been described in connection with the making of copies from a roll of paper it should also be noted that copies may also be made from individual sheets of copy paper with equal effectiveness and rapidity. In the event, the copy paper is in the form of individual sheets, the friction roller 35 would be removed from the apparatus, and the mechanism would be so geared to operate a conventional cut sheet feeder. The apparatus is otherwise operated in a manner similar to its operation when a continuous roll of copy paper is being used.

In actual operation of the apparatus shown forty-five copies have been obtained from a single exposed and developed matrix, while four or five copies is the average number of copies that can be made in accordance with present practice.

To remove the matrix from the drum, the crank 38 is rotated to rotate the drum until the clamping member 26 is in position to be engaged by the opener 16. The opener 16 is then pivoted to open the jaws of the clamping member 26 The matrix is then manually removed in an obvious manner from the surface of the drum.

The drum may either be enclosed in a housing or partially exposed. When the matrix is not immersed in the developing solution, the copy paper is in contact with the matrix, which protects the emulsified surface of the matrix from undue drying when the matrix is traveling outside the developing liquid.

While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as. come within known or customary practice in the art, to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall within the scope of the invention or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. A. machine for reproducing copies from an exposed matrix comprising a tray for holding a developing liquid, a drum rotatable in said tray, a matrix clamping means pivotally attached to the drum, manually operable means for'opening said clamping means to receive a matrix, a rod attached to the clamping means, means fixedly secured relative to said tray and positioned to engage said rod when said drum is rotated in one direction to pivot the opened clamping means into clamping position, means for holding said clamping means in clamping position when said drum is rotated in the opposite direction, and a pressure roller rotatably mounted on said tray, said pressure roller being positioned to press a sheet of copy paper against the surface of a matrix clamped on the rotating drum when said drum is rotated in said opposite direction.

2. A machine for reproducing copies from an exposed matrix comprising a tray for containing a developing liquid, a drum rotatable in said tray, a first gear coaxially attached to said drum, a pressure roller in frictional engagement with the drum, a second gear rotatably mounted on the tray to mesh with the first gear, a feed roller, a third gear secured coaxially to said feed roller and meshing with said second gear, a throw-out linkage pivotally attached to the tray, said feed roller and second and third gears being rotatably mounted on said throw-out linkage, a lever for pivoting said throw-out linkage to move the second gear out of mesh with the first gear, a dog attached to the tray, and means for constantly urging the dog to a position to engage said linkage and hold said second gear out of engagement with the first gear when said lever is moved in one direction, means for rotating said first gear to rotate said drum, and means carried by said drum for disengaging said dog from said linkage so that said second gear engages said first gear when said drum has been rotated in one direction to a predetermined position. 1

3. A machine for reproducing copies from an exposed matrix comprising a tray for containing a developing liquid, a drum rotatable in said tray, a clamping means pivotally mounted on the drum, said clamping means when opened extending away from the surface of the drum, and when closed lying flush with the surface of the drum, manually operable means for opening said clamping means to receive a matrix, means for automatically closing the clamping means in response to the rotation of the drum in one direction to clamp said matrix to said drum, and a rotatable feed roller attached to said tray, said feed roller being positioned to feed a piece of copy paper against the surface of the matrix in response to the rotation of the drum in the other direction.

4. A machine according to claim 3 wherein the means for closing the clamping means is a locking rod which extends diametrically through said drum and which is attached at one end to the clamping means, and a pin attached to the tray for engaging the opposite end of the locking rod.

5. A machine for reproducing copies from an exposed matrix comprising a tray for containing a developing liquid, said tray having spaced longitudinal supporting ridges formed in its bottom interior surface, a cover attached to the top of said tray, said cover having spaced downwardly extending guide members, the top surface of the supporting ridges and the lower surface of the guide members being vertically spaced from each other to form a guideway for a matrix, said tray' having a mouth in the front portion communicating with said guideway, a drum rotatable in said tray, a matrix clamping means pivotally attached to the surface of the drum, said clamping means when closed being flush with the surface of the drum, and when opened extending outwardly from the surface of the drum, said drum being rotatable in one direction so that the spacebetween the surface of the drum and the clamping means when said clamping means is in open position is aligned with the guideway in the tray so that the leading end of a matrix can be fed through said guideway into said space, and means secured in said tray for pivoting the clamping means to a closed clamping position when said drum is rotated through a predetermined angle in the opposite direction.

6. A machine for reproducing copies from an exposed matrix comprising an enclosure for holding a developing liquid, a drum rotatable on said enclosure and positioned so that a portion of it at least passes through said enclosure as the drum rotates, a clamp mounted on said drum for clamping a matrix to said drum, said clamp being movable from open to closed position and vice versa, means in said enclosure positioned to engage said clamp when the clamp is in open position to limit rotation of said drum in one direction, means in said enclosure for guiding a matrix into said clamp when open and when said drum is at its limit position in said one direction, means secured to said enclosure operative automatically to close said clamp when said drum is rotated in the opposite direction through a predetermined angle from said limit position, means for feeding copy paper on top of said matrix as said drum is rotated in said one direction after said clamp has been closed, and means for pressing said copy paper against said matrix as the drum revolves in said one direction after the clamp has been closed.

7. A machine for making copies from an exposed matrix comprising a container for a developing liquid, a drum mounted to rotate through the liquid in said container, a clamp on said drum for securing a matrix on the periphery of said drum, said clamp being movable between open and closed positions, manually-operable means for opening said clamp, means positioned beneath the level of liquid in said container for guiding a matrix to said drum, means for rotating said drum in opposite directions, said drum being rotatable in one direction when said clamp is open to align the open clamp with said guiding means so that the leading end of the matrix is directed by said guiding means into the open clamp between the open clamp and said drum, means positioned in said container to engage and automatically close said clamp when said drum is rotated in the opposite direction through a predetermined angle to clamp the matrix on the drum, and means for feeding different pieces of copy paper on top of said matrix on each revolution of said drum after said clamp has been closed and said drum is rotated again in said one direction whereby copy is transferred successively to different pieces of copy paper on each revolution of said drum without removal of the matrix from said drum.

8. A machine for making copies as claimed in claim 7 wherein said clamp is pivoted on said drum to project beyond the periphery of said drum when opened, and to lie flush with said periphery when closed, and a stop is provided on said container which is beneath the level of liquid in said container and which is positioned to engage said clamp when said clamp is open to limit rotation of said drum in said one direction, thereby to align the open end of the clamp with said guiding means.

9. A machine for making copies as claimed in claim 7 wherein said guiding means is positioned to guide the matrix to said drum along a plane approximately tangential to the periphery of said drum at one side of the axis of notation of said drum, and said feeding means is positioned to guide the pieces of paper to said drum along a plane also approximately tangential to the periphery of said drum but at a point lying at the opposite side of said axis from the first-named plane.

10. A machine for making copies from an exposed matrix comprising a container for a developing liquid, a drum mounted to rotate through the liquid in said container, a clamp on said drum for securing a matrix on the periphery of said drum, said clamp being movable between open and closed positions, manually operable means for opening said clamp, means for guiding a matrix beneath the level of liquid in said container to said drum, means for rotating said drum in opposite directions, said drum being rotatable in one direction, when said clamp is open, to align the open clamp with said guiding means so that the leading end of the matrix is received between the open clamp and said drum, means operative when said drum is rotated through a predetermined angle in the opposite direction to automatically close said clamp, said clamp when closed securing said matrix on the periphery of said drum to rotate with said drum, a pressure roller rotatably mounted on said container to press a sheet of copy paper on top of said matrix as said matrix revolves with said drum in said one direction, a feed roller for feeding sheets of copy paper between said pressure roller and said matrix, means for driving said feed roller from said drum, means for disengaging said driving means when said clamp is open, means for locking said disengaging means in operative position when said clamp is open, and means carried by said drum and operative after said clamp has been closed, when said drum is rotated in said one direction for tripping said locking means out of locking position to permit said driving means to return to driving position.

11. A machine for making copies as claimed in claim wherein said matrix is fed through said guiding means with its exposed surface up, and said drum is rotated in said one direction through part of a revolution, after said clamp has been closed, to pull the Whole matrix from said guiding means into the liquid before a sheet of copy paper is fed on top of said matrix.

12. A machine for reproducing copies from an exposed matrix comprising a container for developing liquid, a drum rotatably mounted in said container that a portion of its peripheral surface, at least, will pass through the liquid in said container as the drum rotates, a clamp pivotally mounted on the periphery of said drum, said clamp when opened extending away from the peripheral surface of said drum and when closed lying substantially flush with said peripheral surface, means positioned in said container and extending beneath the normal level of liquid in said container for guiding a matrix to said drum, and means positioned in said container beneath the normal level of liquid in said container to engage said clamp when opened to limit rotation of said drum in one direction to align the opened clamp with said guiding means whereby said matrix will be directed by said guiding means into the open clamp.

References Cited in the file of this patent UNITED STATES PATENTS 2,195,491 Marchev Apr. 2, 1940 2,374,039 Rockhill Apr. 17, 1945 2,380,744 Ford July 31, 1945 2,573,810 Rundbald Nov. 6, 1951 2,780,973 Nagels Feb. 12, 1957 2,775,933 Malone et a1. Jan. 1, 1957 FOREIGN PATENTS 534,845 Great Britain Mar. 19, 1941 

